1. Field of the Invention
The present invention relates to a method for correcting disc type determination, and in particular to a method that corrects erroneous disc type determination immediately.
2. Description of the Related Art
To quickly read information stored on a disc, optical storage devices must determine disc type quickly and precisely to allow the pickup head to commence reading.
When a disc is inserted into an optical storage device, focusing servo adjusts the focus position of a pickup head and determines the disc type preliminary. Before the operation of ‘track on’ is executed by the tracking servo, a tracking error signal is detected and thereafter normalized. The normalization multiplies the tracking error signal by an appropriate gain to produce a normalized tracking error signal to be processed in subsequent calculation. After the normalization, the optical storage device begins to read the disc with a CD laser beam for CD or a DVD laser beam for DVD. Conventionally, the optical storage device discovers errors in disc type determination when the pickup head cannot read the information stored in the disc. Thereafter the optical storage devices will try different setting modules to make sure the errors (i.e. trial and error method).
However, this conventional method discovers errors belatedly, wasting much time in correcting the mistake.